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Q HOW TO SELECTED THE FILTER PRESS ?
A Please kindly shared us your Slurry be filtrated detial as: Slurry composition, Slurry temperature, PH value, Slurry concentration (dry solid content in slurry) g/L, or %, Solid Particle size (mm), Slurry feed rate (m3/h), Filter press operated hours (h/d), Automation requirement, in as much detail as possible and return to us, JWK look forward to submit to your best proposal.
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Q HOW TO SELECTED THE FILTER PRESS CAPACITY ?
A When estimating the filter press sizing requirements, Firstly determine the customer’s processing requirements, Second select the appropriate filter press chamber volume per cycle that corresponds with the customer’s slurry % dry solids content and cake moisture after filtrated.
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Q WHAT IS THE HIGHEST PRESSURE I CAN PUMP TO FILTER PRESS?
A JWK Filter presses are designed generally for two pressures, 7 and 15 bar (100 and 225 psi), although special filter presses are made for higher pressures. Check the filter press O & M or nameplate to ensure you do not exceed the pressure your filter press was designed for.
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Q HOW DO I CLEAN MY FILTER CLOTHS?
A Use a spatula to scrape cake off the surface. Cake buildup can cause bending of the filter press skeleton. Excessive bending can lead to filter press failure ! Keep the cloths and plates as clean as possible, especially along the sealing surface of filter plates.
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Q HOW CAN I KNOW WHEN FILTER CLOTHS ARE DIRTY ?
A Usually you will need a longer cycle time to achieve the same cake dryness. You may also notice cake or discharge flow water is less.
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Q WHAT IS FILTER CLOTH SPEC?
A In addition the cloth material, and other critical data is “CFM” or cubic feet per minute, which refers to cloth permeability.
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Q How Do I Change Head Plate Cloth
A Unlike intermediate filter cloths, the head-plate (end and tail) cloth do not have a sewn-in center feed eye.
The head plate cloth would be installed as described in the previous question; however, the head-plate cloth must have the center feed hold cut before installation.
To do this, remove the old head cloth by first removing the center feed assembly‘s clip nut. Then, tap the corners of the new end-cloth into the head-plate making sure it is positioned correctly.
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Q What is the best feed pump for a filter press?
A Many pump types are used with good results, depending upon the characteristics of the material being processed. Air diaphragm pumps do not shear flocculated slurries and are the most common type of pump used. An added advantage to this type of pump is that the air drive stalls when filtration is complete.
Positive displacement pumps are used on high pressure filter press.
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Q What is open filtrate discharge?
A Open Discharge is where the filtrate is discharged externally to the filter plate with no drain eyes in the corners of the filter plate.
The filtrate will drain into an open trough (launder) running the length of the Filter Press.
The big advantage is the easy visual identification of a failed filter cloth – that plate will run dirty when compared with the others.
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Q What is closed filtrate discharge?
A Closed Discharge is where the filtrate is discharged internally to corner drain eyes. In this design, all of the filtrate goes to the feed end of the filter press, ideal in instances where the filtrate needs to be contained due to pH or odor. This configuration is required in instances where the filter cake needs to be washed or air-blowing dried.
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Q Can I reduce the filtration cycle time?
A Normally the slurry characteristics determine cycle time. Conditioning of the slurry can improve the cycle time. Thinner cakes will also reduce cycle times and are more easily washed.
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Q How often should change the oil in hydraulic system
A Under normal conditions, you should usually change hydraulic oil once half year, or every 2,000 operating hours.
Under severe conditions, the oil will need to be changed more frequently.
The schedule plan be on O&M for maintenance of hydraulic power unit.
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Q Why the filter plates leaking during the feed process
A If do not made any recent changes to the plate stack (which is the number one reason this might occur), there are several possibilities.
Build-up of solids on the sealing surfaces which will then need to be cleaned.
Check to see if the hydraulic pressure is set to the recommended specifications. If not, make the appropriate adjustment.
Another possibility is that there could be a wrinkle or hole in the filter cloth or the gaskets may be loose.
If you continue to have problems, Touch on JWK.
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Q How do I precoat the filter press
A Precoat and slurry feed are two related applications.
Both of these special applications use diatomaceous earth, cellulose, perlite or fly ash, as a filtering aid when the solids in a slurry are extremely fine and free-filtering.
The filter aid helps to trap the fine solids that otherwise might flow through the filter cloths.
The processes of precoat and slurry feed increase the clarity of the filtrate, provide for higher flow rates, more consistent runs, shorter cycles, dryer cakes, better cake release, and also help to protect and increase the life of the filter cloths.
The precoat process is performed before the slurry is pumped into the filter press. A precoat system consists of a tank, mixer and pump.
The filter aid is mixed with water in the precoat tank.
It is then pumped into the filter press where it coats the filter cloths.
The filter aid rather than the filter cloths becomes your initial filter media.
During a slurry feed the filter aid mixes with the slurry in the holding tank prior to being fed into the filter press.
The filter aid becomes part of the slurry thereby providing a better filter cake.
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Q What can I do to ensure the driest possible filter cake
A Add feed pressure, or membrane squeezing pressure, and Be sure cloths are cleaned as needed and the air blowing system is run for a full cycle.
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Q How long is the filtration cycle time
A Filtration cycle time is dependent on solids loading and can take anywhere
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Q Will I need to replace the plates
A Plates generally last years unless they become cracked, broken or warped. It is good practice to examine the plates during press cleaning and cake discharge.
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Q When do the cloths need to be cleaned or replaced
A The filter cake will begin to become wet, slimy and not as dry. This is indicator that the cloths need to be cleaned. If you have already cleaned the cloths and the process has not changed but you are still getting slimy filter cake, it may be time to replace filter cloths.
Cloth life varies from installation to installation and depends on such variables as frequency of cycles, proper cleaning and maintenance and the type of sludge that is generated.
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Q How often should I change the hydraulic filter
A Whenever you change your oil, you should change your filter.
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Q What is involved in routine filter press maintenance
A Cloth cleaning, cake dumping, check hoses and connections
